#mesoarchean

The environment they were found in apparently has evidence of being a sand-blasted desert with occasional streams, which is what I have shown here. I've also included mountains because I'm think there were some mountains near Witwatersrand around this time.

The Mesoarchean Era started 3.2 billion years ago and lasted until 2.8 billion years ago. With the crust continuing to cool and volcanism still rampant, tectonic plates shift around the globe, tearing continents apart and putting them back together. Below the ocean's surface, cyanobacteria thrived and formed diverse microbial ecosystems. They would feed on the carbon dioxide rich in the atmosphere and pump out lots of oxygen. A technique so effective that it would be passed along to modern plants. These growing ecosystems would drastically effect the global climate. The increase in oxygen would cool the planet and form the first glaciation at the poles.

(via https://www.youtube.com/watch?v=0tYjd_CfoS8)

2.500 milhões de anos, as cianobactérias surgem em abundância. Também conhecidas como algas verdes azuladas, são organismos aquáticos procariotas que produzem energia através de fotossíntese, libertando como desperdicio, oxigénio. ○22mm

3 biliões de anos, forma-se o supercontinente Ur. Precedido por Vaalbara, agora despedaçado, foi durante os seus primeiro tempos, muito possivelmente, o único na Terra.